Feeling clueless on how to defend the clueless

Having Asperger Syndrome has made me sympathetic to the plight of others who are similarly socially clueless.  So sometimes when I hear others criticizing or expressing awkwardness about dealing with a socially clueless person I want to jump in and defend the reputation of the clueless person.

Years ago while I was at a library a group of my classmates gathered around and started talking about how a woman we all knew had asked one of them out on a date.  The problem was the boy in question was on a date with another girl when this woman asked him out.  They were confused by her lack of tact and expressed frustration that this woman kept doing things like that.  I happened to know that this woman also had Asperger syndrome.  It would have been so convenient to have just said "She's a little mentally disabled when it comes to social norms so cut her some slack."  But this is a sensitive issue and its not good to out someone else especially if you aren't absolutely confident that the results will be emotionally safe for the person you are outing.  So I just said something like "I'd give her the benefit of the doubt."  Since at least some of the people around me knew about my having Asperger Syndrome I think I might have even gone as far as saying "I'd cut her some slack just like you would if I made a social mistake."  I don't know if she ever got her date with the young man she asked out, but I kind of doubt it.

Recently at work I've overheard similar conversations of frustration regarding someone who is socially clueless.  Someone who I know has tentatively self diagnosed themselves as Asperger Syndrome.  Unfortunately, this man often tends to go beyond simply being clueless.  He also tends towards being cluelessly and loudly offensive.  Making sexually judgmental comments about his coworkers daughters, absurdly racist statements, bigoted statements about homosexuals, and other unpleasant things to deal with.

And I just don't know what to do.  He's a nice enough guy once you get past the rougher edges and if he doesn't drive you crazy first with the more absurd things he talks about.  I'd love to step up and say "I'm sorry you feel he was frustrating, but he just doesn't understand social politeness"  Because it often goes beyond politeness in style to issues of offensiveness in content.  And I can't make any excuse for those statements.  They are just there.  But I wish I could do something more.  It makes me feel clueless.